Footwear

ABSTRACT

A multi-segment sole structure for use in footwear may be constructed of rigid segments positioned to correspond to one or more weight-bearing areas of the foot and flexible segments positioned to correspond to one or more less weight bearing or flexible areas of a foot. The flexibility may be provided by elastomeric materials, living hinges, or mechanical hinges. The sole structure may include a lower support base which may have hollow segments alternating with rigid or flexible supports. The rigid segments of the sole may be supported by rigid supports. The rigid segments may be wood. The conjoined interfaces may be perpendicular to the surface. A rigid segment may overhang a flexible segment or a flexible segment may overhang a rigid segment.

BACKGROUND OF THE INVENTION

The invention relates to footwear and specifically to hybrid soles for footwear.

DESCRIPTION OF THE RELATED TECHNOLOGY

Footwear refers to garments worn on the feet, which typically serve the purpose of protection against adversities of the environment such as ground textures and temperature. Footwear in the manner of shoes therefore primarily serves the purpose to ease locomotion and prevent injuries. Footwear can also be used for fashion and adornment as well as to indicate the status or rank of the person within a social structure. Socks and other hosiery are typically worn additionally between the feet and other footwear for further comfort and relief. Cultures have different customs regarding footwear. These include not using any in some situations, usually bearing a symbolic meaning. This can however also be imposed on specific individuals to place them at a practical disadvantage against shod people if they are excluded from having footwear available or are prohibited from using any. This usually takes place in situations of captivity, such as imprisonment or slavery, where the groups are among other things distinctly divided by whether or not footwear is being worn. Footwear has been in use since the earliest human history, archeological finds of complete shoes date back to the Chalcolithic (ca. 5000 BCE). Some ancient civilizations, such as Egypt and Greece however saw no practical need for footwear due to convenient climatic and landscape situations and used shoes primarily as ornaments and insignia of power.

The Romans saw clothing and footwear as unmistakable signs of power and status in society, and most Romans wore footwear, while slaves and peasants remained barefoot. The Middle Ages saw the rise of high-heeled shoes, also associated with power, and the desire to look larger than life, and artwork from that period often depicts bare feet as a symbol of poverty. Depictions of captives such as prisoners or slaves from the same period well into the 18th century show the individuals barefooted almost exclusively, at this contrasting the prevailing partakers of the scene. Officials like prosecutors, judges but also slave owners, or passive bystanders were usually portrayed wearing shoes. During the Middle Ages, men and women wore pattens, commonly seen as the predecessor of the modern high-heeled shoe, while the poor and lower classes in Europe, as well as slaves in the New World, were usually barefoot. In the 15th century, chopines were created in Turkey and were usually 18-20 cm (7-8 inches) high. These shoes became popular in Venice and throughout Europe, as a status symbol revealing wealth and social standing.

During the 16th century, royalty such as Catherine de Medici and Mary I of England began wearing high-heeled shoes to make them look taller or larger than life. By 1580, men also wore them, and a person with authority or wealth might be described as, well-heeled. In modern society, high-heeled shoes are a part of women's fashion and are widespread in certain countries around the world.

For many people, supportive shoes can make a significant difference in overall foot health and how people feel each day. It is vital that feet have all the support they need to function at their best. One of the most common causes of foot pain is wearing unsupportive shoes that leave essential elements of the feet unsupported and improperly aligned. Over time, this can cause pain and strain that can limit mobility. Orthopedic shoes are intended to provide support. Shoes that lack sufficient support can exacerbate an existing foot problem. For example, without the proper arch and heel support, those who suffer from plantar fasciitis will experience stretching and tearing on surfaces of the plantar fascia which will worsen inflammation that causes heel pain and discomfort. Unsupportive footwear, when combined with foot problems, can create an endlessly frustrating cycle that makes it difficult to heal and attain comfort and relief. To break that cycle, it's vital to wear supportive footwear so that you can get relief from cumbersome and prohibitive foot problems. Supportive footwear can help improve balance and optimize stability. Many shoes do not have the supportive features needed to maintain natural alignment.

Cushioning and flexibility are other aspects of footwear required for comfort and utility. To effectively and easily walk or run some flexibility is required in footwear. However, there has been a trade-off between support and flexibility. More flexible shoes are less supportive. More supportive shoes are less flexible. Similarly cushioning may be important to foot comfort, but the same trade-off applies. Cushioning may result in greater flexibility but may reduce support.

Modern footwear may be made up of leather or plastic, and rubber. In fact, leather was one of the original materials used for the first versions of a shoe. The soles can be made of rubber or plastic, sometimes having a sheet of metal inside. Roman sandals had sheets of metal on their soles so that it would not bend out of shape. More recently, footwear providers like Nike, have begun to source environmentally friendly materials.

U.S. Pat. No. 7,426,792 shows a cushioning system for athletic footwear that provides a large deflection for cushioning the initial impact of a foot-strike, a controlled stiffness response, a smooth transition to bottom-out, and stability, and more specifically to a system that allows for customization of these response characteristics by adjustment of the orientation of a single bladder or insert in a resilient foam material. This system is designed to address impact areas limited to one or two bladders but suffers the drawback of not being able to address the flexibility of the sole in relation to the flexibility of a foot.

A living hinge or integral hinge is a thin flexible hinge (flexure bearing) made from the same material as the two rigid pieces it connects. It is typically thinned or cut to allow the rigid pieces to bend along the line of the hinge. The minimal friction and very little wear in such a hinge make it useful in the design of microelectromechanical systems, and the low cost and ease of manufacturing make them quite common in clamshell containers and other disposable, recyclable packaging, for example, the hinge on the lid of a Tic Tac® box.

Plastic living hinges are typically manufactured in an injection molding operation that creates all three parts at one time as a single piece, and if correctly designed and constructed, it can remain functional over the life of the part. Thermoforming can also produce hinged products. Polyethylene, polypropylene, acrylonitrile butadiene styrene (ABS) are materials used for living hinges, due to excellent fatigue resistance. Living hinges may be made from an extension of the parent material (such as polypropylene plastic). They are the thin section of plastic that acts as a connection between two larger plastic sections. Since they are very thin, they may be made from flexible polypropylene and may be able to rotate about one axis 180 degrees or more—potentially for millions of cycles without breaking. Contrary to most hinges which involve multiple parts assembled in a traditional mechanism, living hinges are not a separate entity. They can be described as a purposeful fault line at a predetermined point in the material which is carefully designed such that it doesn't fail after repeated bending. The bottle cap on a ketchup bottle is an example of a living hinge.

Living hinges may be made using a subtractive process such as by CNC machining. Living hinges may also be formed by injection molding. An additive process such as 3D printing may also be used to form a living hinge.

A living hinge can be created in wood using various methods. A variant on the kerf bend can be used to create living hinges in laser-cut wood. The technique is used for making light-duty hinges with large radii. It is possible to create a living wood joint by hand, but the result is less accurate.

U.S. Ser. No. 10/918,160B2, the disclosure of which is incorporated by reference herein, shows a sole structure for an article of footwear comprises a unitary midsole having a first portion and a second portion rearward of the first portion. A bottom surface of the unitary midsole defines a groove extending from a medial side to a lateral side of the unitary midsole, and a top surface of the unitary midsole defines a slit disposed over the groove and extending from the medial side to the lateral side. The unitary midsole forms a living hinge at the groove and the slit, with the living hinge connecting the first portion to the second portion so that the first portion and the second portion are selectively pivotable relative to one another at the living hinge between a first orientation and a second orientation. The groove is wider in the first orientation than in the second orientation, and the slit is wider in the second orientation. The footwear has a sole structure having a front sole portion, a rear sole portion, and a living hinge extending transversely across the sole structure from a medial side to a lateral side of the sole structure and connecting the front sole portion to the rear sole portion. The article of footwear has a divided footwear upper including a front upper portion and a separate rear upper portion. The front upper portion is fixed to the front sole portion and defines at least the forefoot region of the footwear upper, and the rear upper portion is fixed to the rear sole portion and defines the heel region of the footwear upper. The front sole portion and the rear sole portion are selectively pivotable relative to one another at the living hinge between a use position and an access position. In the use position, the front upper portion and the rear upper portion together define a foot-receiving cavity and an ankle opening, and the rear upper portion overlaps the front upper portion at a medial side of the sole structure and at a lateral side of the sole structure. In the access position, the front upper portion and the rear upper portion are spaced apart from one another so that the ankle opening is larger than in the use position. Accordingly, the article of footwear with the divided upper portion may enable hands-free foot entry in the access position, while the overlapping front and rear upper portions provide lateral stability to the upper in the use position.

SUMMARY OF THE INVENTION

According to an advantageous feature, the use of the design makes it possible to use hard or rigid materials such as wood in shoes yet still maintain the flexibility needed for comfortable walking and movement. With a hybrid sole as described, it is an object to obtain the advantages of support and flexibility. This is to get the experience of standing and walking on hard, flat surfaces no matter what the actual surface. This is important as the posture and walking technique is usually significantly better on hard, flat surfaces.

The area, shape, size, and height of the portions of the insole could be vary based on design, material, and functional objectives and considerations. Further, even though flat surfaces have been illustrated in the figures, any of the portions could have contours based on design, material, and functional objectives and considerations. For example, the segmented sole with rigid segments may be used for shoes having a drop i.e., with the heel being higher than the toe. Additionally, any of the segments may have contours, for example, for providing arch support.

As used in this application, a segment refers to any of the parts into which a thing may naturally be divided, separated, or demarked. Each component of an object having distinct components may be a segment. In an object having two or more areas exhibiting different properties, each area may be a segment regardless of whether the areas are integral. A section is meant to refer to a segment that is integral to an adjoining segment. A component is meant to refer to a segment of an object that is non-integral with other segments of the object.

It is an object to have a hybrid sole for footwear that uses hard materials such as wood, plastic, etc. in the sole to support the wearer, while still being able to maintain flexibility of the shoe sole. The hybrid sole as described herein has advantages over prior wood soles. Cork soles are comparatively soft and flexible. Other sandals with wood soles are not flexible.

A multiple segment sole structure for use in footwear may include at least one rigid segment positioned to correspond to an area of a wearer's foot that is weight-bearing and at least one flexible segment conjoined to a rigid segment positioned and sized to correspond to an area of a wearer's foot that is less weight-bearing or flexible. The rigid segment may be wood. The rigid segment may be conjoined to the flexible segment at a conjoined interface and wherein the conjoined interface may be configured to be at an angle to a normal surface of said segments and said flexible segment overhangs said rigid segment at the conjoined interface. However, any given segment could overhang another or the interface between segments could be normal to the surface depending on design and performance objectives. The flexible segment may be an elastomeric material such as an EVA foam. The rigid segment may correspond to a forefoot region of the sole structure. The flexible segment may correspond to a midfoot region of said sole structure, and the second rigid segment may correspond to a rearfoot region of said sole.

The multiple segment sole structure may have segments conjoined in other configurations. The interface between conjoined segments may be simple or complex. A simple interface could be oriented normally to the surface of the sole. As described, one or more of the flexible segments may overhang an adjacent rigid segment at a conjoined interface. One or more of the rigid segments may overhang an adjacent flexible segment at a conjoined interface. A complex interface may be used also. A complex interface allows a greater surface area of adjacent segments to bond and may provide greater mechanical strength.

A cover layer may be over the conjoined segments and an underbase layer may be under the conjoined segments. When a cover or underbase layer are present, the segments could be adhered to the cover layer and or the underbase layer, possibly in addition to or in place of being adhered to each other.

For example, the segments could be individually glued to an underbase layer to hold them in the desired position without them being glued to each other.

In a five-segment configuration, a first rigid segment may be conjoined to a first flexible segment at a first conjoined interface and a second rigid segment conjoined to the first flexible segment at a second conjoined interface and conjoined to a second flexible segment at a third conjoined interface, A third rigid segment may be conjoined to the second flexible segment at a fourth conjoined interface. The first conjoined interface, second conjoined interface, third conjoined interface, and fourth conjoined interfaces may be oriented generally perpendicular to the length of the sole. One or more of the interfaces may be straight-line interfaces.

One or more of the conjoined interfaces may be complex interfaces, such as s-shaped curve interfaces, zig-zag interfaces, key hole interfaces, or other configurations. For example, in a five-segment configuration, the first conjoined interface and the fourth conjoined interface may be s-shaped curve interfaces; and the second conjoined interface and the third conjoined interface may be straight-line interfaces. An interface may exhibit a zigzag shape or any type of interlocking configuration. These configurations may increase strength and durability due to enhanced surface area and potentially a mechanical interference to separation.

The sole structure may have a flexible sole layer of a size and shape generally suitable to accommodate a perimeter of a wearer's foot and exhibiting a continuous, discontinuous, or partial frame with one or more recesses. Rigid inserts may be in the recesses. At least a portion of the perimeter of one or more of the recesses may exhibit an undercut contour and wherein the rigid inserts may have an external perimeter shape generally matching a contour of the recesses. The flexible sole layer may be the midsole, the insole, or other suitable layer of the sole.

Parts of the insole, midsole, and/or outsole, including inserts, may be customized and/or interchangeable to target conditions e.g., foot pain. People could experiment with barefoot walking with flat and hard portions on their morning walks but then replace those portions with those with more cushion and support for use during the rest of the day.

The outsole, midsole, and the insole body/frame could all be separate components that are joined using fasteners or adhesives. Or the outsole, midsole, and the insole body/frame could consist of a single unit e.g., injection molded foam or carved rubber. The interchangeable portions of the insole and the optional, removable insole cover could then be installed separately. Generally, the outsole of a shoe is the very bottom of the shoe, the part that contacts the ground. The insole is the part of the shoe that the foot rests upon. The midsole is the part or parts of the sole that lie between the insole and the outsole.

The sole may be configured with slots to permit insertion of segments having desired characteristics to allow a degree of customization to the soles. For example, inserts could be slid in from one or both sides of the sole. The surface of the slots and the base of the interchangeable portions could have features such as contours, grooves, or protrusions (the counterpart being holes) to help secure the interchangeable portions firmly in place. The slots could also be used to secure add-on portions that sit on top of the sole surface e.g., if the user wants to have reinforced arch support.

It is an object to allow for use of “smart pads” as interchangeable Portions of a hybrid sole.

The same design of the insole with interchangeable portions can also support the use of “smart” portions in place of the regular interchangeable portions. These smart portions can be self-sufficient, in that they could contain all the electronics and machinery necessary to offer the desired feature set. A modular approach allows users to get more value out of the purchase of footwear. For example, being able to take advantage of newer technology without having to plan for it in advance when making the initial purchase. The smart portions may contain basic components such as:

-   -   1. Processing chips     -   2. Storage     -   3. Battery     -   4. Communication components e.g., Bluetooth and Wi-Fi

The smart portions could contain a variety of sensors such as:

-   -   1. Accelerometer     -   2. Gyroscope     -   3. Pressure sensors     -   4. Thermometer     -   5. Heart Rate sensors     -   6. Humidity sensors     -   7. GPS chips

The smart portions could further contain components such as:

-   -   1. Heat generators     -   2. Haptic feedback     -   3. Vibrators     -   4. Sound/Audio     -   5. Lights     -   6. Massager

Use Cases & Application:

-   -   1. Standing posture correction     -   2. Gait correction     -   3. Sporting applications e.g., running technique     -   4. Gait analysis for healthcare applications e.g., tracking         dementia development.

All other considerations that apply to regular interchangeable portions also apply to their smart counterparts e.g., the surface of the slots and the base of the interchangeable portions could have features such as contours, grooves, or protrusions (the counterpart being holes) to help secure the interchangeable portions firmly in place.

It is a further object to provide smart soles with interchangeable portions, including where the entire insole layer becomes interchangeable as opposed to just individual portions of the insole. Smart portions (segments inserted or present in a hybrid insole) could be self-contained, or they could rely on a central unit for things such as power, storage, wireless communication, and so on. The Central Unit could have a variety of components housed in a single enclosing unit or the components could simply be interconnected without being in the same enclosure or some combination thereof. The connectors that connect the smart portions to the central unit may protrude out, they could be flush with the top surface or even be depressed within the contacting surface. For the scenario with just one smart portion acting as the insole, there could be one or more than one connector. This kind of modular design would allow users to upgrade their smart portions without having to replace the entire unit. This could help lower the cost of upgrading to the latest compatible feature set for the end user.

All other considerations that apply to regular interchangeable portions also apply to their smart counterparts e.g., the surface of the slots and the base of the interchangeable portions could have features such as contours, grooves, or protrusions (the counterpart being holes) to help secure the interchangeable portions firmly in place.

An enhanced configuration may include an enhanced midsole with hollow portions. A sole with rigid segments admits of further modifications to reduce weight and enhance energy return i.e., absorbing and returning more of an athlete's kinetic output; flexibility; stability; and durability. The midsole may have hollow areas oriented perpendicular to the Sagittal Plane of the foot. This orientation may align the midsole hollow areas with the rigid and flexible areas within the midsole segment. The hollow areas of the midsole make the structure more flexible and reduce the material used, thereby reducing weight. The size, shape, and location of the hollow areas may be based on the design and functional objectives while also factoring in other considerations such as the materials used. The stability and durability of the midsole with hollow areas may be enhanced by a retaining layer, such as the outsole continuously closing the hollow areas. Furthermore, encapsulation of the outer periphery may seal the hollow areas and prevent water and dirt from entering the cavities. The encapsulation material may be EVA, PU. Or other suitable materials and the materials may be transparent, translucent, or opaque. In addition, the midsole itself and sole portion may have any appropriate shape including being thicker and broader underneath the heel and tapering towards toe box. The sole may also be of uniform thickness throughout.

Trapezoidal prism-shaped segments may be located directly underneath the flexible sole segments and/or under solid-to-flexible interfaces to improve stability and durability. The hollow areas or segments between hollow areas may have shapes that are variations of trapezoidal prisms, for example with curved lateral faces.

Parallelepiped-shaped segments between hollow areas can further improve the energy return while potentially compromising on stability. The orientation can be determined based on the objective. The shape of segments between hollow areas may be forward-leaning (heel-to-toe orientation) to optimize for running. Backward-leaning parallelepiped-shaped segments may be placed at the forward tip of the shoe for counteracting the force when the wearer lands on the toes to improve the stability and durability of the sole. Cuboid-shaped segments (not shown) between hollow areas may also be used to provide stability and durability.

An alternative to the use of conjoined rigid and flexible segments made of different materials would be the use of solid materials that are made flexible in the desired locations using living hinges (also called integral hinges). A living hinge or integral hinge is a flexible hinge (flexure bearing) made from the same material as the two rigid pieces it connects. It is typically thinned or cut to allow the rigid sections to bend along the line of the hinge. This alternative approach allows for use of a midsole or insole constructed of a single substrate. The substrate may incorporate living hinges at the lines of flexibility. Such a substrate may be created by injection molding, a subtractive process such as by using a CNC machine or laser to cut portions of the substrate, or an additive process such as 3D printing. The substrate having lines of flexibility enabled by a living hinge may be customized for an individual using measurement of specific parameters of the individual's foot. Based on the measurements a substrate may be cut by a laser or a CNC machine at the location(s) indicated by the measurements. In an additive process, a custom 3D printed substrate may be fabricated according to individual needs or measurements. Mass production may be facilitated by an injection molding process. The substrate may be fabricated with appropriately placed living hinges. The substrate may be supported by the hollow under-soul features as discussed above. Various configurations of living hinges may be used. Examples include a straight (or kerf), bowling pin, beehive, cross, hex, or diamond configuration for a natural hinge.

A recess-mounted mechanical hinge, such as a butler hinge, also called a butler tray hinge, may be used to connect adjacent rigid segments instead of a flexible segment or living hinge. Options include a single hinge, an extended hinge, or more than one hinge to permit a line of flexibility.

A multi-segment sole structure for use in footwear may be constructed of two or more segments conjoined and having an upper support surface and an opposing lower base surface. At least one of the segments may be a rigid segment positioned to correspond to a weight-bearing area of a wearer's foot. At least one of the segments may be a flexible segment conjoined to the rigid segment. The sole structure may include two or more co-planar rigid segments and may include a flexible segment that is co-planar with the rigid segments and conjoined to consecutive rigid segments. At least the flexible segment may be arranged in an area to correspond to a less-weight bearing area of the foot. The rigid segments may be wood. The rigid segments may be conjoined to a flexible segment at a conjoined interface and the conjoined interface may be at an angle to the upper support surface. A flexible segment may overhang a rigid segment, or a rigid segment may overhang a flexible segment at the conjoined interface. The flexible segment may be an elastomeric material. A rigid segment may be located to correspond to a forefoot region of the sole structure. A flexible segment may be located to correspond to a midfoot region of the sole structure. A second rigid segment may be conjoined to a first flexible segment and the second rigid segment may be located to correspond to a rearfoot region of the sole.

A first rigid segment may be conjoined to a first flexible segment at a first conjoined interface located along a front edge of the first flexible segment and the first flexible segment may overhang the second rigid segment at a second conjoined interface located along a rear edge of the first flexible segment. A cover layer may be over the conjoined segments and an under base layer may be under the conjoined segments.

A first flexible segment may be conjoined to a first rigid segment at a first conjoined interface located along a front edge of the first flexible segment and a second rigid segment may be conjoined to the first flexible segment at a second conjoined interface located along a rear edge of the first flexible segment and conjoined to a second flexible segment at a third conjoined interface along a front edge of the second flexible segment. A third rigid segment may be conjoined to the second flexible segment at a fourth conjoined interface along the rear edge of the second flexible segment. The first conjoined interface, the second conjoined interface, the third conjoined interface, and the fourth conjoined interface may be oriented generally perpendicular to the surface of the sole. At least one flexible segment may be a living hinge segment having a thickness that approximates a thickness of an adjacent rigid segment. The upper surfaces of the rigid and flexible segments may be generally smooth and uninterrupted by thinning of material to form a living hinge. The flexible segments may be surface mounted, recessed hinges such as butler tray hinges. The conjoined interfaces may be straight-line interfaces. The conjoined interfaces may be s-shaped curve interfaces. The first conjoined interface and the fourth conjoined interface may be s-shaped curve interfaces, while the second conjoined interface and the third conjoined interface may be straight-line interfaces. An under-base layer may be provided under the conjoined segments. The under-base layer may include one or more rigid segments supporting a rigid segment or supporting an interface between a rigid segment and a flexible segment. The under base layer may include a plurality of substantially transverse supports alternating with hollow areas. One or more of the transverse supports may be trapezoidal prism supports or inverted trapezoidal prism supports. The trapezoidal prism supports may be located to support the flexible segments. The trapezoidal prism supports may be located to support the rigid segments. The transverse supports may be forward-leaning or backward-leaning parallelepiped supports.

A sole structure for footwear may include a flexible sole layer sized and shaped to accommodate a perimeter of a wearer's foot and may have a continuous frame. One or more recesses may be provided to receive rigid inserts. The recesses may have an undercut contour and the rigid inserts may have an external perimeter shape generally matching a contour of the recesses. The inserts may include sensors and may be connected to a processor with storage and a communications interface.

Various objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, along with the accompanying drawings in which like numerals represent like components.

Moreover, the above objects and advantages of the invention are illustrative, and not exhaustive, of those that can be achieved by the invention. Thus, these and other objects and advantages of the invention will be apparent from the description herein, both as embodied herein and as modified in view of any variations which will be apparent to those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a two-segment sole.

FIG. 1A shows a side view of an embodiment of a two-segment sole according to FIG. 1 .

FIG. 1B shows a side view of an embodiment of a two-segment sole according to FIG. 1 .

FIG. 2 shows an embodiment of a hybrid sole having three segments.

FIG. 2A shows a side view of an embodiment of a hybrid sole having three segments according to FIG. 2 .

FIG. 2B shows a side view of a second embodiment of a hybrid sole having three segments according to FIG. 2 .

FIG. 3 shows a hybrid sole having five segments.

FIG. 3A shows a side view of an embodiment of a hybrid sole having five segments according to FIG. 3 .

FIG. 3B shows a side view of second embodiment of a hybrid sole having five segments according to FIG. 3 .

FIG. 4 shows a three-segment hybrid sole with “S” shaped interfaces rather than straight line interfaces.

FIG. 5 shows an alternative embodiment to that illustrated in FIG. 3 for a five-segment hybrid sole.

FIG. 6A shows an embodiment of a hybrid sole in cross section.

FIG. 6B shows an alternate configuration to FIG. 6A.

FIG. 7A shows an alternative configuration of the hybrid sole shown in FIG. 6A.

FIG. 7B shows an alternative configuration of the hybrid sole shown in FIG. 6B.

FIG. 8 shows a further alternative embodiment of a hybrid sole.

FIG. 9 shows a hybrid sole for a smart shoe.

FIG. 10 shows an embodiment with approximate dimensions for a sole suitable for US shoe size M 9.5-10.

FIG. 11 shows an embodiment with approximate dimensions for a sole suitable for US shoe size M 9.5-10.

FIG. 12 shows a “slide” type of sandal that incorporates a hybrid sole.

FIGS. 13A, 13B, 13C, and 13D show alternative configurations for an enhanced midsole with hollow portions.

FIG. 14 shows an embodiment with flexible living hinge portions.

FIG. 15 shows a “straight” living hinge configuration.

FIG. 16 shows a “bowling pin” living hinge configuration.

FIG. 17 shows a “beehive” living hinge configuration.

FIG. 18 shows a “cross” living hinge configuration.

FIG. 19 shows a “hex” living hinge configuration.

FIG. 20 shows a “diamond” living hinge configuration.

FIG. 21 shows an alternative embodiment of a hybrid sole.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

Before the present invention is described in further detail, it is to be understood that the invention is not limited to the embodiments described, as such may, of course, vary. The terminology used herein is for the purpose of describing embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.

Where a range of values is provided, each intervening value between the upper and lower limit of that range and any other stated or intervening value in that stated range is encompassed within the range of values. The upper and lower limits of any stated smaller ranges within the larger range may independently be included in the smaller ranges, subject to any specifically excluded limit in any stated range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, a limited number of the exemplary methods and materials are described herein.

Throughout the description of the embodiments, it is understood that the reference to a wearer is not a reference to an individual wearer or a precise size. It is intended that the sole may be made in multiple sizes, i.e., shoe sizes and may not be custom fit to an individual wearer. In this description, reference to length is intended to refer to the distance along a line between the edge of the sole somewhere near the heel area to an opposing edge somewhere near the toe area. It is not intended to be a precise anatomical reference. Throughout this disclosure, reference to width is intended to refer to any point along one side of the sole to an opposing point on the other side of the sole. The orientation of a width is generally perpendicular to the orientation of the length. Neither orientation is intended to be precise unless precisely specified in anatomical terms, for example, the anatomical axis of a foot is defined as the line connecting the first metatarsal heads. The origin of the foot local coordinate system situates on the upper ridge of the calcaneus bone. The position of the functional axis of a foot is defined by its intersection point with the XOY plane of the foot coordination system, whereas the location of the anatomical axis is determined by its intersection point with the XOY plane of the foot coordination system. See Raychoudhury, Sivangi & Hu, Dan & Ren, Lei. (2014), Three-Dimensional Kinematics of the Human Metatarsophalangeal Joint during Level Walking, Frontiers in Bioengineering and Biotechnology, 2:73 (10.3389/fbioe.214.00073) the disclosure of which is expressly incorporated by reference herein.

FIG. 1 shows a two-segment sole. The sole 10 is the base for footwear. The axial length of the sole 10 extends from the edge of the heel 11 to the edge of the toe area 12. The sole is designed as a layer structure having one or more horizontal layers. The layers may be flat or contoured. A contoured layer surface may conform to the contour of a wearer's foot or have contours designed to affect the wearer's foot, i.e., an elevated portion behind a wearer's toe can serve as a toe spreader.

The soles as described in the various embodiments are composed of a segmented layer. The layers may each be the size of the entire sole of the footwear. Segments may be conjoined at an interface. The interface is the boundary between two connected segments in a single layer. The interface may be formed, and segments connected by adhesive, by welding, by being connected to a common or connected layer without being mechanically joined to each other. FIG. 1 shows an embodiment with a rigid forefoot segment 13 and a flexible segment 14 in the mid foot and rear foot region of the sole 10. The sole structure may include a cover 15 optional which serves as an in-sole and/or optional under base 16 which may serve as an outsole. FIG. 1A shows a cross section of the embodiment of FIG. 1 with a perpendicular interface 17 a. FIG. 1B shows a cross section of the embodiment illustrated in FIG. 1 with a slanted interface 17 b. Interface 17, 17 a, or 17 b may be positioned so that the rigid segment supports a weight-bearing portion and the flexible segment is at a flexible portion of an average user's foot. A slant interface 17 b may be provided so that a portion of the flexible material of flexible segment 14 overhangs at least a portion of the rigid material of rigid segment 13. The rigid material may be wood or other suitable material for a footwear sole and the flexible material may be elastomeric.

FIG. 2 shows an embodiment of a hybrid sole 20 having three segments. According to FIG. 2 , the sole has a rigid segment 21 in the forefoot, a flexible segment 22 in the midfoot, and a rigid segment 23 in the rearfoot region. The forefoot segment 21 abuts the midfoot segment 22 at a forward interface 24. The midfoot segment 22 abuts the rearfoot segment 23 at a rearward interface 25. The forward interface 24 and the rearward interface 25 are positioned so that the weight-bearing portion of the forefoot is on the forefoot segment 21 and the weight-bearing portion of the rearfoot is on the rearfoot segment 23. The midfoot segment 22 is a flexible segment and is not one of the primary weight-bearing segments. FIG. 2A shows a cross-section of the embodiment of FIG. 2 with a perpendicular forward interface 24 a and a perpendicular rearward interface 25 a. FIG. 2B shows a cross-section of the embodiment of FIG. 2 but has a slanted forward interface 24 b and a slanted rearward interface 25 b. FIGS. 2A and 2B show a cover layer 26 and an under base layer 27. The cover layer may be flexible and may be adhered to all three segments. Similarly, the under base may be flexible and adhered to all three segments. The slanted interfaces 24 b and 25 b shown in FIG. 2B may be arranged with the flexible material of midfoot segment 22 overhanging the abutting portion of the forefoot segment 21 at the forward interface 24. In addition, the flexible material of the midfoot segment 22 may overhang the original material of the rearfoot segment 23 at the rearward interface 25 b.

FIG. 3 shows a hybrid sole having five segments. The five-segment hybrid sole 30 includes, starting from the forward portion of the foot and continuing to the rear portion of the foot, a first rigid segment 31 of rigid material, a second segment 32 of flexible material, a third segment 33 of rigid material, a fourth segment 34 of flexible material and a fifth segment 35 of rigid material. The first segment 31 is joined to the second segment 32 at a first interface 36. The second segment 32 is joined to the third segment 33 at a second interface 37. The third segment 33 meets the fourth segment 34 at a third interface 38. The fourth segment 34 joins the fifth segment 35 at a fourth interface 39. As described above, FIG. 3A shows a cross-section of the sole 30 with perpendicular interfaces 36 a, 37 a, 38 a, and 39 a between segments 31 a, 32 a, 33 a, 34 a, and 35 a respectively. FIG. 3B shows a cross section of the sole 30 where the edges of the flexible segments 32 b overhang the adjoining portions of first segment 31 b and third segment 33 b. The edges of the flexible segment 34 b overhang the adjoining portions of third segment 33 b and fifth segment 35 b.

FIG. 4 shows a three-segment hybrid sole similar to FIG. 2 , but with “S” shaped interfaces rather than straight-line interfaces. FIG. 4 has a rigid segment 43 at the forefoot area. A flexible segment 44 is in the midfoot area and a rigid segment 45 is in the rearfoot area. A forward interface 46 may be “S” shaped to define a slightly larger lobe supporting the balls of a wearer's foot. The rearward interface 47 roughly corresponds in contour to the forward interface 46. The interfaces 46 and 47 may be perpendicular as shown in FIG. 2A or may be slanted as shown in FIG. 2B. In the case of slanted interfaces, it is preferable to have the material of the more flexible segment overhang the material of the rigid segments.

FIG. 5 shows an alternative embodiment to that illustrated in FIG. 3 for a five-segment hybrid sole 50. The five-segment hybrid sole 50 may include a first segment 51 at the front of the foot made of a rigid material. A second segment 52 may be of a flexible material and may abut segment 51. A third segment 53 may be a rigid segment and may abut the edge of second segment 52. A fourth segment 54 may be arranged to abut the third segment 53 and may be of a flexible material. A fifth segment 55 may be the rearward most segment which is rigid and abuts the edge of the fourth segment 54. The second segment 52 may be arranged to abut the first segment 51 and the third segment 53. The fourth segment 54 may be arranged to abut the third segment 53 and the fifth segment 55. There is an interface 56 between first segment 51 and second segment 52. There is an interface 57 between second segment 52 and third segment 53. There is a third interface 58 between third segment 53 and fourth segment 54. There is a fourth interface 59 between fourth segment 54 and fifth segment 55. The interfaces 56, 57, 58, and 59 may be perpendicular to the foot surface or may be slanted to have the flexible material overhang the rigid material of abutting segments. FIG. 5 shows a “S” shaped first interface 56 and an “S” shaped fourth interface 54. The “S” shaped interface 56 includes a lobe to support the ball of a user's foot. The lobe is balanced by an oppositely curved portion towards the outside of a user's foot. The fourth interface is shown to track the first interface in FIG. 5 .

FIG. 6A shows an embodiment of a hybrid sole 60 in cross section. The main body 61 of hybrid sole 60 may be of a flexible material. The main body may include recesses 62 and 63 in the rearfoot area and the forefoot area respectively. A rigid insert 64 may be received in recess 62 and a rigid insert 65 may be received in recess 63. The rigid inserts have the effect of providing rigid support allowing flexible support in areas of the foot bearing less weight.

FIG. 6B shows an alternate configuration to FIG. 6A. FIG. 6B shows recesses 66 having an undercut portion 67. The recesses are configured to receive mating inserts 68 and 69. The inserts 68 and 69 may advantageously be rigid. The recesses can have one or more inclined edges that mate with overhanging portions of the flexible in one of the sole 60. The hybrid sole 60 may have an optional cover 70. The cover 70 may be planar or contoured and may be flexible. The covers may assist in retaining the inserts 64, 65, 68, and 69 in the flexible sole base 61.

FIGS. 7A and Bb show alternative configurations of the hybrid soles 60 shown in FIGS. 6A and 6B. Both the flexible sole base 61 a shown in FIGS. 7A and 61 b shown in FIG. 7B may have recesses with perpendicular walls as shown in FIG. 6A or recesses with one or more overhanging walls as shown in FIG. 6B. FIG. 7A shows a forward insert 71. The forward insert 71 may have a straight-line rearward transverse edge 72. The forward insert 71 may have walls that are perpendicular to the major surface of the sole or may have one or more walls that are inclined. Similarly, the rearward insert 73 may have a forward straight-line transverse edge 74. The rearward insert 73 may have walls that are perpendicular to the major surface of the sole or may have one or more walls that are inclined. FIG. 7B shows a forward rigid insert 75 with a rearward “S” shaped edge 76 and a rearward rigid insert 77 having a forward “S” shaped edge 78. The forward insert 75 may have walls that are perpendicular to the major surface of the sole or may have one or more walls that are inclined. Similarly, rearward insert 77 may have walls that are perpendicular to the major surface of the sole or may have one or more walls that are inclined. The hybrid soles shown in FIGS. 6A, 6B, 7A, and 7B may optionally have cover layers and/or under base layers. The under base layers mentioned in these and the other embodiments described may have a tread shape suitable for various uses and the cover layers may be flat or contoured for comfort and/or orthopedic reasons.

The hybrid soles may be provided with interchangeable inserts. The interchangeable inserts may have various rigidities or compositions. In addition, the rigid inserts may function as a housing for electronic components including various sensors, power storage and transmission. For example, one or more of the inserts may contain motion sensors, batteries and/or piezoelectric sensors and generators along with capacitive or chemical storage. In this way, the action of walking can generate sufficient energy to drive the sensors, temporarily store sensor output, and communicate, for example, by IOT Bluetooth communications to a receiver for processing.

FIG. 8 shows a further alternative embodiment of a hybrid sole 80. The sole 80 may have a flexible base 81 with one or more recesses 82, 83 for receiving rigid inserts 84, 85. The flexible sole base 81 may have one or more lower recesses 86, 87 for receiving firmer inserts 88, 89. Insert segments 88, 89 may be of a firmer material than flexible sole portion 81 and may be used to provide better support in the underneath regions of transition at one or more of the edges of inserts 84, 85. The firm material may be denser than the flexible segment. For example, a neoprene rubber. The hybrid sole may optionally include a cover layer 15 and/or an under base 16.

FIG. 9 shows a hybrid sole 90 for a smart shoe. The flexible base 91 may include recesses 92 for rigid inserts as described above. The flexible base 91 may include connectors 93 to electrically interface with electrical components which may be housed in “smart pads” 94. The smart pads 94 may include sensors and other components. Alternatively, as shown in the embodiment illustrated in FIG. 9 , other components such as a CPU 95, storage 96, communication interface 97, and battery 98 may be included in a separate unit 99 received in a further recess 100 in the flexible base 91. A connector 101 may be provided on a side surface of the flexible base 91 to provide a communications interface and/or charging for the battery/electrical storage component contained in separate unit 99. An under base (not shown) may be provided with or without firmer support inserts. In addition, a cover 102 may be provided on the upper surface of the hybrid sole 90. The cover 102 may be removeable to allow access to the recesses 92 and/or 100.

FIGS. 10 and 11 are intended to show an embodiment with approximate dimensions for a sole suitable for US shoe size M 9.5-10. The hybrid sole 105 is provided to support a user's foot 106. The user's foot 106 is shown for illustration purposes only and forms no part of the invention. The hybrid sole 105 is provided with five rigid segments 106, 107, 108, 109, and 110 separated by flexible segments 111, 112, 113, and 114. The overall length of the hybrid sole may be 10½ inches, and the width across the widest portion of the forefoot area of the sole may be 4 inches. The length of the first rigid segment 106 may be 1 and ¾ inches. The length of the second rigid segment 107, may be 1⅛ inches. The length of the third rigid segment 108 may be 15/16ths of an inch. The length of the fourth rigid segment 109 may be 2 and 3/16ths of an inch, and the length of the fifth rigid segment 110 may be 3 inches. The length of the first flexible segment 111 and second flexible segment 112 may be ¼ inch each and the length of the third segment 113 and fourth flexible segment 114 may be ½ inch each. Each of the rigid segments 106, 107, 108, 109, and 110 may be ⅛-inch wooden boards. The flexible segments 111, 112, 113, and 114 may be ⅛ inch thick and may be rubber material. An underbase layer 115 may be provided which is a 1/16-inch rubber sheet.

The interfaces between the segments shown in FIG. 11 are approximately perpendicular to the midline sagittal plane of the foot. A description of anatomical features of a foot can be found in Atlas of Anatomy, Anne M. Gilroy, Brian R. McPherson, Lawrence M. Ross, Thieme Publishers, ISBN 160406062X, incorporated by reference herein. See Chapter 26: Ankle & Foot. According to the embodiment shown in FIG. 11 , the flexible segments 111, 112, 113, and 114 are aligned to cooperate with the planes of flexibility of a foot which run substantially perpendicular to the midline sagittal plane of the foot. The first flexible segment 111 may be positioned near the rearward end of the forefoot, for example, slightly forward of the base of the second proximal phalanx. The second flexible segment 112 may be arranged near the forward end of the midfoot, for example, in a plane perpendicular to the midline sagittal plane that is near the head of the fourth metatarsal. The third flexible segment 113 may be in a plane perpendicular to the midline sagittal plane which approximately bisects the metatarsal bones, close to the midline of the second and third metatarsals. The fourth flexible segment 114 may be located in a plane perpendicular to the midline sagittal plane in the forward portion of the hind foot. For example, near the intersection of the navicular and the talus.

The embodiment illustrated in FIG. 11 provides flexibility and support for the wearer by providing flexible segments ahead and behind the principal planes of flexibility of the foot and supporting the principal weight-bearing portions of the foot. For example, the first flexible segment 111 may be arranged above the base of the proximal phalanx of the big toe. The second flexible 112 may be arranged below the head of the first metatarsal. The third flexible segment 113 may be arranged below the head of the fifth metatarsal. The fourth flexible segment 114 may be arranged below the tuberosity of the fifth metatarsal.

According to an embodiment for determining sole specifications, the sole specifications may be based on foot length and width. For example, a given specification may serve individuals with foot length and width within the corresponding ranges determined for the specification in question. The measurements may be determined by tracing the outline of the feet. Then the length may be measured from the back/central part of the heel to the end of the longest toe. Width may be measured across the widest part of the foot (usually across the ball of the foot). Foot length and width may be correlated to shoe size or foot size. For a given individual, specifications may be measured in terms of distances of the various anatomical features (e.g., tuberosity of the fifth metatarsal) from the back part of the heel. The positions of the anatomical features can be marked on the paper at the same time as tracing the foot outline. The anatomical features used for deriving the specifications can be observed visually or they could be felt by hand. Other methods that could be used for measuring foot length and width, as well as the locations of the various anatomical features, include X-Rays, 3D Scanning, Plantar Pressure Data/Image, and so on.

When designing and making shoes for an individual, the approach outlined would suffice. However, when designing and manufacturing shoes for a larger set of people, that is, people with the same foot size but possibly varying anatomical features, a statistic-based system and process may be used to optimize fit and comfort across a larger user base. For example, first, establish the various foot sizes, with a foot size determined by ranges of foot length and width or their approximate values. Foot sizes could be established using existing standards. One mechanism for this may be by using a Brannock Foot Measuring Instrument as shown in U.S. Pat. No. 1,725,334. Alternatively, measurements from a diverse set of individuals may be captured and grouped to establish custom purpose sizes. Custom purpose sizes may have sufficient granularity so that when footwear is constructed by custom sizes, and acceptable percentage of consumer population will be satisfied with the fit and feel of at least one size footwear. Second, for a given size, measurements may be taken from a statistically sufficient number of individuals to represent a target audience. One method for determining a sufficient sample size is power analysis to determine the size of a pool of individuals to represent the target audience (e.g., with or without any feet-related conditions, etc.). Third, measurements for a given size are then evaluated to determine the specifications. For this, statistical methods, anatomical considerations, or a combination of these and other methods could be used. For example, averages (mean values), median, max, min, etc. could be used for determining the specifications. Outliers may be filtered out using statistical methods

A sole may be configured by optimizing the location of the interfaces between segments. The locations specified in this paragraph may be customized for a single wearer or may be based on the statistical position of the anatomical characteristics of a pool of individuals having the size (standard or custom size). The locations of the interfaces relative to the anatomical features may be determined empirically, or at least confirmed empirically. The positions may vary based on the materials used, the thickness of the layers, and the intended use of the footwear. Considering the embodiment in FIG. 3 , a five-segment sole may have its interfaces oriented perpendicular to a midline sagittal plane. The first interface 36 may be positioned slightly forward of the location of the proximal phalanx of the big toe. The second interface 37 may be positioned slightly rearward of the location of the head of the first metatarsal. The third interface 38 may be positioned to correspond to a position slightly rearward of the head of the fifth metatarsal. The fourth interface 39 may be positioned to correspond to the position slightly rearward of the location of the tuberosity of the fifth metatarsal

FIG. 12 shows a “slide” type of sandal which incorporates the hybrid sole as described herein. Hybrid sole 120 includes a flexible base material 121 having transverse slots 122. Rigid slats 123 may be received and retained within the slots 122. The retention of the slats 123 may be by a friction fit. Alternatively, the slots 122 may be slight smaller than the size of the slat 123 intended to be inserted through the slot 122. The flexible base 121 in this case must be sufficiently flexible to allow deformation to accommodate the insertion of the slats 123 through the smaller slots 122. A sandal of this design will have areas of flexibility between slots 122 and rigidity imparted by slats 123 between the areas of flexibility. The slots 122 may be fully or partially closed on one side of the sole, for example the outside. There may also be a structure to make removal of the slats easier, for example groves in the sole body for access to the slat or a protrusion that may be used to remove a slat. The slotted arrangement of a hybrid sole 120 with received slats 123 is not limited to slide type sandals, but may be present in other footwear, including athletic shoes, dress shoes and casual shoes and other types of sandals.

FIGS. 13A, 13B, 13C, and 13D show alternative configurations for an enhanced midsole with hollow portions. A sole with rigid segments admits of further modifications to reduce weight and enhance energy return i.e., absorbing and returning more of an athlete's kinetic output; flexibility; stability; and durability. The midsole embodiments shown in FIGS. 13A-D have hollow areas oriented perpendicular to the Sagittal Plane of the foot. This orientation aligns the midsole hollow areas with the rigid and flexible within the midsole segment. The hollow areas of the midsole make the structure more flexible and reduces the material used, thereby reducing weight. The size, shape, and location of the hollow areas may be based on the design and functional objectives while also factoring in other considerations such as the materials used. The stability and durability of the midsole with hollow areas may be enhanced by a retaining layer, such as an outsole or under base continuously closing the hollow areas. Furthermore, encapsulation of the outer periphery may seal the hollow areas and prevent water and dirt from entering the cavities. The encapsulation material may be EVA, PU. Or other suitable materials and the materials may be transparent, translucent, or opaque. In addition, the midsole itself and sole portion may have any appropriate shape including being thicker and broader underneath the heel and tapering towards toe box. The sole may also be of uniform thickness throughout.

FIGS. 13A-D show configurations of footwear 130 having hollow portions 131 arranged in the midsole 132 and a continuous outsole layer 133. Segments 135 provide stability and improve energy return. Trapezoidal prism shaped segments 136 may be located directly underneath the flexible sole segments and/or under solid-to-flexible interfaces to improve stability and durability. FIGS. 13A, 13B, and 13D show hollow areas 134 having a trapezoidal prism shape. The hollow areas or segments between hollow areas may have shapes that are variations of trapezoidal prisms, for example with curved lateral faces.

Parallelepiped shaped segments 138 and 139 between hollow areas can further improve the energy return while potentially compromising on stability. The orientation can be determined based on the objective. As shown in the figures, the shape of segments between hollow areas may be forward-leaning 138 (heel-to-toe orientation) to optimize for running. Backward-leaning parallelepiped shaped segments 139 may be placed at the forward tip of the shoe for counteracting the force when the wearer lands on the toes to improve the stability and durability of the sole. Cuboid-shaped segments (not shown) between hollow areas may also be used to provide stability and durability.

FIG. 14 shows an embodiment with flexible living hinge portions 142, 144, 146, and 148. The embodiment shown in FIG. 14 is an alternative to alternating conjoined rigid and flexible segments. FIG. 14 shows an integral substrate for use as a layer of the sole, for example, a midsole or insole with rigid sections 141, 143, 145, 147, and 149. Living hinge sections 142, 144, 146, and 148 separate the rigid sections 141, 143, 145, 147, and 149. The flexible sections 142, 144, 146, and 148 may be sized and located according to custom measurements for individual users or may be in optimized locations and have optimized widths over a set of users as explained above.

FIG. 15 shows a “straight” living hinge configuration that may be used in an embodiment as disclosed herein.

FIG. 16 shows a “bowling pin” living hinge configuration that may be used in an embodiment as disclosed herein.

FIG. 17 shows a “beehive” living hinge configuration that may be used in an embodiment as disclosed herein.

FIG. 18 shows a “cross” living hinge configuration that may be used in an embodiment as disclosed herein.

FIG. 19 shows a “hex” living hinge configuration that may be used in an embodiment as disclosed herein.

FIG. 20 shows a “diamond” living hinge configuration that may be used in an embodiment as disclosed herein.

FIG. 21 shows an alternative embodiment of a hybrid sole 210. The hybrid sole 210 may include a first rigid segment 211 connected to a second rigid segment 212 by two hinges 215. The hinges 215 may be surface mounted or received in recesses in the rigid segments so that the upper surface of the hybrid sole is not interrupted by the hinges 215. The hybrid sole 210 may be a midsole and have an optional under base (not shown) and/or a cover (not shown). The hybrid sole 210 may have more than two segments. The embodiment illustrated in FIG. 21 shows a third rigid segment 213 and a fourth rigid segment 214. The second rigid segment is connected to the third rigid segment by two hinges 215. The third rigid segment is connected to the 4th rigid segment 214 by hinge 215. One, two, or more hinges 215 may be utilized to connect adjacent rigid segments. The hinges 215 may be butler hinges, also known as butler tray hinges.

It should be noted that a hybrid sole is not limited to utilizing the same flexible connecting structure to provide flexibility between adjacent rigid segments or sections. A hinge 215 may be utilized between one set of adjacent rigid segments and a different flexible connection structure, such as segments made of flexible material conjoined between adjacent rigid segments as well as living hinge sections may be used between other sets of adjacent rigid segments. In addition, the embodiment illustrated in FIG. 21 may also be provided with a further layer having hollow areas and segments between and defining the hollow areas, as illustrated in FIGS. 13A-13D.

It must be noted that as used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural referents unless the context clearly dictates otherwise.

All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited. The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates, which may need to be independently confirmed.

The invention is described in detail with respect to preferred embodiments, and it will be apparent from the foregoing to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and the invention, therefore, as defined in the claims, is intended to cover all such changes and modifications that fall within the true spirit of the invention.

It should be apparent, however, to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the disclosure. Moreover, in interpreting the disclosure, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. 

The invention claimed is:
 1. A multi segment sole structure for use in footwear comprising: two or more segments conjoined and having an upper support surface and an opposing lower base surface; at least one of said segments is a rigid segment positioned to correspond to an area of a wearer foot which is weight-bearing; at least one of said segments is a flexible segment conjoined to said rigid segment positioned and sized to correspond to an area of a wearer foot that is less weight bearing.
 2. The multi segment sole structure according to claim 1 wherein said rigid segment is wood.
 3. The multi segment sole structure according to claim 1 wherein said rigid segment is conjoined to said flexible segment at a conjoined interface and wherein said conjoined interface is configured to be at an angle to said upper support surface and wherein said flexible segment overhangs said rigid segment at said conjoined interface.
 4. The multi segment sole structure according to claim 1 wherein said flexible segment is an elastomeric material.
 5. The multi segment sole structure according to claim 1 wherein said rigid segment is a first rigid segment and is located to correspond to a forefoot region of said sole structure, said flexible segment is a first flexible segment, and further comprising a second rigid segment conjoined to said first flexible segment.
 6. The multi segment sole structure according to claim 5 wherein said first rigid segment is conjoined to said first flexible segment at a first conjoined interface located along a front edge of said first flexible segment and wherein said first flexible segment overhangs said second rigid segment at a second conjoined interface located along a rear edge of said first flexible segment.
 7. The multi segment sole structure according to claim 1 further comprising a cover layer over said conjoined segments and an under base layer under said conjoined segments.
 8. The multi segment sole structure according to claim 1 wherein: said rigid segment is a first rigid segment and said flexible segment is a first flexible segment conjoined to said first rigid segment at a first conjoined interface located along a front edge of said first flexible segment; and further comprising a second rigid segment conjoined to said first flexible segment at a second conjoined interface located along a rear edge of said first flexible segment and conjoined to a second flexible segment at a third conjoined interface along a front edge of said second flexible segment; a third rigid segment conjoined to said second flexible segment at a fourth conjoined interface along a rear edge of said second flexible segment; and wherein said first conjoined interface, said second conjoined interface, said third conjoined interface, and said fourth conjoined interface are oriented generally perpendicular to a length of said sole.
 9. The multi segment sole structure according to claim 8 wherein at least one of said flexible segments is a living hinge segment having a thickness that approximates a thickness of an adjacent rigid segment.
 10. The multi segment sole structure according to claim 9 wherein at least one of said living hinge segments exhibits gaps arranged to enhance flexibility of said living hinge segment.
 11. The multi segment sole structure according to claim 8 wherein at least one of said flexible segments is one or more surface mounted recessed hinges.
 12. The multi segment sole structure according to claim 1 wherein at least one of said flexible segments is a living hinge segment having a thickness that approximates a thickness of an adjacent rigid segment.
 13. The multi segment sole structure according to claim 8 wherein one or more of said conjoined interfaces are straight line interfaces.
 14. The multi segment sole structure according to claim 8 wherein one or more of said conjoined interfaces are complex interfaces.
 15. The multi segment sole structure according to claim 8 wherein said first conjoined interface and said fourth conjoined interface are s-shaped curve interfaces and said second conjoined interface and said third conjoined interfaces are straight line interfaces.
 16. The multi segment sole structure according to claim 8 further comprising a cover layer over said conjoined segments.
 17. The multi segment sole structure according to claim 8 further comprising an under base layer under said conjoined segments.
 18. The multi segment sole structure according to claim 17 wherein said under base layer further comprises a firm segment supporting an interface between a rigid segment and a flexible segment.
 19. The multi segment sole structure according to claim 17 wherein said under base layer further comprises a plurality of substantially transverse supports alternating with hollow areas.
 20. The multi segment sole structure according to claim 19 wherein one or more of said transverse supports are trapezoidal prism supports.
 21. The multi segment sole structure according to claim 20 wherein one or more of said trapezoidal prism supports are located to support said flexible segments.
 22. The multi segment sole structure according to claim 20 wherein one or more of said trapezoidal prism supports are inverted trapezoidal prism supports located to support said rigid segments.
 23. The multi segment sole structure according to claim 19 wherein one or more of said transverse supports are forward-leaning parallelepiped supports.
 24. The multi segment sole structure according to claim 19 wherein one or more of said transverse supports are backward-leaning parallelepiped supports.
 25. A sole structure for footwear comprising: a flexible sole layer of a size and shape generally suitable to accommodate a perimeter of a wearer's foot and exhibiting a continuous frame and one or more recesses; and one or more rigid inserts located in said one or more recesses.
 26. The sole structure according to claim 25 wherein at least a portion of a perimeter of said one or more recesses exhibit an undercut contour and wherein said rigid inserts have an external perimeter shape generally matching a contour of said recesses.
 27. The sole structure according to claim 25 wherein one or more of said inserts further comprises sensors. 